Asymmetric introgression between sympatric molestus and pipiens forms of Culex pipiens (Diptera: Culicidae) in the Comporta region, Portugal

<p>Abstract</p> <p>Background</p> <p><it>Culex pipiens </it>L. is the most widespread mosquito vector in temperate regions. This species consists of two forms, denoted molestus and pipiens, that exhibit important behavioural and physiological differences. The evolutionary relationships and taxonomic status of these forms remain unclear. In northern European latitudes molestus and pipiens populations occupy different habitats (underground <it>vs</it>. aboveground), a separation that most likely promotes genetic isolation between forms. However, the same does not hold in southern Europe where both forms occur aboveground in sympatry. In these southern habitats, the extent of hybridisation and its impact on the extent of genetic divergence between forms under sympatric conditions has not been clarified. For this purpose, we have used phenotypic and genetic data to characterise <it>Cx. pipiens </it>collected aboveground in Portugal. Our aims were to determine levels of genetic differentiation and the degree of hybridisation between forms occurring in sympatry, and to relate these with both evolutionary and epidemiological tenets of this biological group.</p> <p>Results</p> <p>Autogeny and stenogamy was evaluated in the F1 progeny of 145 individual <it>Cx. pipiens </it>females. Bayesian clustering analysis based on the genotypes of 13 microsatellites revealed two distinct genetic clusters that were highly correlated with the alternative traits that define pipiens and molestus. Admixture analysis yielded hybrid rate estimates of 8-10%. Higher proportions of admixture were observed in pipiens individuals suggesting that more molestus genes are being introgressed into the pipiens form than the opposite.</p> <p>Conclusion</p> <p>Both physiological/behavioural and genetic data provide evidence for the sympatric occurrence of molestus and pipiens forms of <it>Cx. pipiens </it>in the study area. In spite of the significant genetic differentiation between forms, hybridisation occurs at considerable levels. The observed pattern of asymmetric introgression probably relates to the different mating strategies adopted by each form. Furthermore, the differential introgression of molestus genes into the pipiens form may induce a more opportunistic biting behaviour in the latter thus potentiating its capacity to act as a bridge-vector for the transmission of arboviral infections.</p

Influence of the addition of alpha or gamma-cyclodextrin on the formation of free films in the polymethacrylates eudragit® FS30D

Free films were obtained by the combination of a polymer EudragitTM FS30D and oligosaccharides (alpha or gamma-CDs), by a casting process. The films were characterized by DSC, TGA, FTIR and SEM. The influence of composition was available by WVT and swelling measurements experiments. The DSC, TGA and FTIR characterized the films as immiscible in all composition studied. The results have shown that the addition of oligosaccharide to EudragitTM FS30D promoted changes to both the water vapour permeability and hydration properties of the films. The changes were shown to be dependent on the increase in the concentration oligosaccharides added to the free film. The films EudragitTM FS30D and oligosaccharides alpha or gamma-CDs obtained are regarded as being suitable for preventing the premature release of drugs in the upper part of the gastrointestinal tracts and present great interest in the application as biodegradable carriers for modified oral drug delivery systems.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Forage Intake of \u3ci\u3eNellore\u3c/i\u3e Steers Grazing a \u3ci\u3eCajanus Cajan\u3c/i\u3eLegume-Grass Intercropped Pasture

This study evaluated forage, supplement, and total (forage + supplement) dry matter intake (DMI, expressed as kg/day and as percentage of average live weight, %ALW) of Nellore steers in different production systems, including a Cajanus cajan (Pigeon pea) legume-grass intercropped pasture by using external (titanium dioxide, TiO2) and internal (indigestible neutral detergent fiber, iNDF) markers. The experiment was carried out at Embrapa Southeast Livestock, São Carlos, SP, Brazil, in the rainy (January) and dry (July) seasons of 2021. Eighteen animals Nellore steers were randomly distributed into three treatments with three replications (1.5 ha paddocks each): 1) degraded pasture of Urochloa decumbens cv. Basilisk (DEG); 2) Intercropped legume-grass pasture composed by U. decumbens cv. Basilisk, U. brizantha cv. Marandu and Cajanus cajan cv. BRS Mandarin limed and fertilized with P, K, S, micronutrients (INT) and 3) mixture pasture of U. decumbens cv. Basilisk and U. brizantha cv. Marandu limed and fertilized with P, K, S, micronutrients and 200 kg N-urea ha-1 year-1 (REC). The statistical model considered treatment and season as fixed effects, and the treatment×season interaction was tested. Data were submitted to analysis of variance (PROC MIXED) and means were compared by the Fisher test at 5%. Significant treatment×season interaction was found (P \u3c 0.05). During the rainy season lower values of forage and total DMI were found for the INT treatment when compared to REC. However, during the dry season, the treatment with Pigeon pea inclusion (INT) presented higher values of forage and total DMI. The DEG and REC system steers reduced their DMI from the rainy season to the dry season, even receiving a mineral energetic-protein supplement with urea, while the INT steers maintained DMI between seasons without receiving the energetic-protein supplement. These results highlight the potential of including Pigeon pea in pasture-based systems, especially during the dry season when tropical grasses present low nutritional quality and forage availability

Search for new neutral Higgs bosons through the H → ZA→ ℓ+ℓ−b b ¯ process in pp collisions at √s = 13 TeV

This paper reports on a search for an extension to the scalar sector of the standard model, where a new CP-even (odd) boson decays to a Z boson and a lighter CP-odd (even) boson, and the latter further decays to a b quark pair. The Z boson is reconstructed via its decays to electron or muon pairs. The analysed data were recorded in proton-proton collisions at a center-of-mass energy s = 13 TeV, collected by the CMS experiment at the LHC during 2016, corresponding to an integrated luminosity of 35.9 fb−1. Data and predictions from the standard model are in agreement within the uncertainties. Upper limits at 95% confidence level are set on the production cross section times branching fraction, with masses of the new bosons up to 1000 GeV. The results are interpreted in the context of the two-Higgs-doublet model. [Figure not available: see fulltext.]

Study of the B +→ J / ψ Λ ¯ p decay in proton-proton collisions at √s = 8 TeV

A study of the B +→ J / ψ Λ ¯ p decay using proton-proton collision data collected at s = 8 TeV by the CMS experiment at the LHC, corresponding to an integrated luminosity of 19.6 fb−1, is presented. The ratio of branching fractions B(B+→J/ψΛ¯p)/B(B+→J/ψK∗(892)+) is measured to be (1.054 ± 0.057(stat) ± 0.035(syst) ± 0.011(B))%, where the last uncertainty reflects the uncertainties in the world-average branching fractions of Λ ¯ and K*(892) + decays to reconstructed final states. The invariant mass distributions of the J / ψ Λ ¯ , J/ψp, and Λ ¯ p systems produced in the B +→ J / ψ Λ¯ p decay are investigated and found to be inconsistent with the pure phase space hypothesis. The analysis is extended by using a model-independent angular amplitude analysis, which shows that the observed invariant mass distributions are consistent with the contributions from excited kaons decaying to the Λ ¯ p system. [Figure not available: see fulltext.

Search for a heavy Higgs boson decaying to a pair of W bosons in proton-proton collisions at √s = 13 TeV

A search for a heavy Higgs boson in the mass range from 0.2 to 3.0 TeV, decaying to a pair of W bosons, is presented. The analysis is based on proton-proton collisions at s = 13 TeV recorded by the CMS experiment at the LHC in 2016, corresponding to an integrated luminosity of 35.9 fb−1. The W boson pair decays are reconstructed in the 2ℓ2ν and ℓν2q final states (with ℓ = e or μ). Both gluon fusion and vector boson fusion production of the signal are considered. Interference effects between the signal and background are also taken into account. The observed data are consistent with the standard model (SM) expectation. Combined upper limits at 95% confidence level on the product of the cross section and branching fraction exclude a heavy Higgs boson with SM-like couplings and decays up to 1870 GeV. Exclusion limits are also set in the context of a number of two-Higgs-doublet model formulations, further reducing the allowed parameter space for SM extensions. [Figure not available: see fulltext.

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE